Where any of the land specified in a general vesting declaration has become vested in an acquiring authority under Part III of this Act, any person who, in consequence thereof, is relieved from any liability (whether in respect of a rentcharge, rent under a tenancy mortgage interest or any other matter) and makes any payment as in satisfaction or in part satisfaction of that liability shall, if he shows that when he made the payment he did not know of the facts which constituted the cause of his being so relieved, or of one or more of those facts, be entitled to recover the sum paid as money had and received to his use by the person to whom it was paid.